I bought my betta when he was very very small 7 months ago which leads me to believe hes about 8 months old. I also bought a Betta kit with him small tank but he always seemed happy with it! I regularly change his water once a week sometimes sooner! and feed him Tetra's BettaMin Food. I am usually always around him if I'm not in class or at work and he's very energetic.

This past week I've noticed his gills has become alittle swollen and hes starting to loose colour he's also sitting at the bottom of the tank in a vertical position and hasn't eaten in acouple days !!!

I have a picture of him here, that i just took as you can see he's sitting upwards some one please help

Doubtless of what pet stores might say or advertise, that betta kit is far too small to keep a betta healthy in long-term. I would very strongly suggest you do a 100% water change right away. You need a 2 gallon minimum for keeping a betta healthy in long-term, as well as a reliable heater at 78 degrees. The water changes you did in that sized tank aren't enough for him. In that size, you should be doing a 50% change on one day and a 100% on the other if you want to keep the water conditions okay for him.

If he is having issues with swimming, do you have his riginal cup he came in? you can float the cup in the tank so he can easily get to the surface to get air.

Those marina tanks are .5 gallons, right? I would upgrade him to at least a gallon but bigger would be even better. One of the main reasons being that a larger tank is easier to heat and requires less care then a smaller one.

i am not sure what would cause him to be in that odd position but a heater would be a plus since they are tropical fish.

Doubtless of what pet stores might say or advertise, that betta kit is far too small to keep a betta healthy in long-term. I would very strongly suggest you do a 100% water change right away. You need a 2 gallon minimum for keeping a betta healthy in long-term, as well as a reliable heater at 78 degrees. The water changes you did in that sized tank aren't enough for him. In that size, you should be doing a 50% change on one day and a 100% on the other if you want to keep the water conditions okay for him.

I'm still kinda new at this, and i don't know any betta fish owners to know that it was too small , i will DEFINITELY look at getting a bigger tank ASAP !!

How much do you feed him?
What is his tank temperature? Its winter, and it looks like you dont have a heater, how warm is your room? He might be too cold.

the "Crystals" are just air bubbles cause i've been changing his water every other day since he's been like this and i just cleaned it before i took the photo! When i got him they never gave me the original glass they took him out and put him in a bag! i feed him a very small amount everyday or sometimes every other day depending on his behavior, i don't over feed him or under feed him and my room is a little over room temp!

If he is having issues with swimming, do you have his riginal cup he came in? you can float the cup in the tank so he can easily get to the surface to get air.

Those marina tanks are .5 gallons, right? I would upgrade him to at least a gallon but bigger would be even better. One of the main reasons being that a larger tank is easier to heat and requires less care then a smaller one.

i am not sure what would cause him to be in that odd position but a heater would be a plus since they are tropical fish.

I do use water conditioner :)
When i see him move alittle it seems like he will always go back in that vertical position and stop i haven't seen him swim much . I'm pretty sure they are .5 gallons i will look into a new tank ASAP!!! i just wish i knew what was wrong with him i hate to see him lay down at the bottom of the tank all day, usually when i would get home he'd notice me and swim around

Thank you everyone so much for your help about this! i hope i can figure out whats wrong with him if i need to get certain drops or something i hate to see him like this! :( I'm going to get a bigger tank ASAP !

if your room is only a little bit over room temp, which means your room is about 70 degrees, which also means his tank is only about 65-68 degrees. Thats way too cold, he'll die if left like that for long. He needs to be in 75-80 degrees water. He can survive 72-75, but still not ideal.

if you dont have a heater, try to bag some hot water and float it in his tank, and wrap his tank with thick towels.

Get a heater asap

when you change his water, do you sit the water for a bit so that the temperature evens out? If the new water temperature has more than a 2 degrees difference, then he may be in shock (especially if he was weak from the cold water already)

I do use water conditioner :)
When i see him move alittle it seems like he will always go back in that vertical position and stop i haven't seen him swim much . I'm pretty sure they are .5 gallons i will look into a new tank ASAP!!! i just wish i knew what was wrong with him i hate to see him lay down at the bottom of the tank all day, usually when i would get home he'd notice me and swim around

You need water conditioner. The chemicals in the water are dangerous to fish and will compromise and/or kill your fish with prolonged exposure.